This invention relates generally to the substantial reduction of thermal distortion of a continuous casting quench surface. Specifically, this invention provides for lateral and radially unrestrained thermal growth of a hoop-like quench surface of a quench wheel in the continuous casting of glassy alloy filaments.
Extruding a molten alloy from a pressurized crucible through a nozzle onto a rotating quench surface is one of several technologically significant methods available for the continuous casting of continuous glassy alloy filaments, as representatively shown in M. Narasimhan, U.S. Pat. No. 4,142,571 "Continuous Casting Method for Metallic Strips" issued Mar. 6, 1979 hereby incorporated by reference. Typically, such filaments are continuously cast as thin strips, as required to achieve the extreme quench rates in quenching a molten alloy to the glassy state.
To maintain transverse cross-sectional constancy along the length of the strip as cast, it is essential that a geometrically stable quench surface be provided. In this regard, a substantial problem, referred to as "crowning", has been encountered, whereby thermal distortion of the hoop-like quench surface of the quench wheel causes the quench surface to bow radially outward. This distortion is due in part to the fact that the hot quench surface is restrained along its periphery by the cool side disk of the quench wheel ("discontinuity stress"). Thus, in steady-state continuous casting with the quench wheel at thermal equilibrium, the bowing of the quench surface is undesirably induced in the transverse cross-sectional shape of the cast filament.